Cdc6-Induced Conformational Changes in ORC Bound to Origin DNA Revealed by Cryo-Electron Microscopy
The eukaryotic origin recognition complex (ORC) interacts with and remodels origins of DNA replication prior to initiation in S phase. Here, we report a single-particle cryo-EM-derived structure of the supramolecular assembly comprising Saccharomyces cerevisiae ORC, the replication initiation factor Cdc6, and double-stranded ARS1 origin DNA in the presence of ATP{gamma}S. The six subunits of ORC are arranged as Orc1:Orc4:Orc5:Orc2:Orc3, with Orc6 binding to Orc2. Cdc6 binding changes the conformation of ORC, in particular reorienting the Orc1 N-terminal BAH domain. Segmentation of the 3D map of ORC-Cdc6 on DNA and docking with the crystal structure of the homologous archaeal Orc1/Cdc6 protein suggest an origin DNA binding model in which the DNA tracks along the interior surface of the crescent-like ORC. Thus, ORC bends and wraps the DNA. This model is consistent with the observation that binding of a single Cdc6 extends the ORC footprint on origin DNA from both ends.
- Research Organization:
- BROOKHAVEN NATIONAL LABORATORY (BNL)
- Sponsoring Organization:
- NATIONAL INSTITUTE OF HEALTH
- DOE Contract Number:
- AC02-98CH10886
- OSTI ID:
- 1043399
- Report Number(s):
- BNL--97032-2012-JA; 400412000
- Journal Information:
- Structure, Journal Name: Structure Journal Issue: 3 Vol. 20; ISSN 0969-2126
- Country of Publication:
- United States
- Language:
- English
Similar Records
Cryo-EM structure of a helicase loading intermediate containing ORC–Cdc6–Cdt1–MCM2-7 bound to DNA
Structure of the active form of human origin recognition complex and its ATPase motor module
Journal Article
·
Sun Jul 14 00:00:00 EDT 2013
· Nature Structural & Molecular Biology
·
OSTI ID:1088204
Structure of the active form of human origin recognition complex and its ATPase motor module
Journal Article
·
Sun Jan 22 23:00:00 EST 2017
· eLife
·
OSTI ID:1343989